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Micellar structures from medicinal mushrooms are self-growing, fibrous, polymeric structures that can be successfully functionalized with various bioactive substances. Moreover, micellar structures can successfully mimic the extracellular matrix of human body tissues. Therefore, they can be used as novel biomaterials in tissue engineering and wound healing. On the other hand, fruit by-products, such as mango peels, are mainly discarded but represent a renewable source from which products with exceptional added value can be obtained. The aim of our study was to determine the antimicrobial properties of functionalized micellar structures obtained from medicinal mushrooms such as Ganoderma lucidum and Pleurotus ostreatus. The adsorption method was used to functionalize the micellar structures with natural mango peel extract (MPE) obtained by an ultrasound-assisted extraction method. In addition, the antimicrobial activity of the functionalized micellar structures was validated using a disk diffusion method. The results of our study show a successful functionalization of micellar structures with natural MPE with a loading efficiency of up to 50-60% and a release rate of 73-96%. Moreover, the antimicrobial properties of the micellar structures from the two selected medicinal mushrooms were successfully determined against the tested pathogenic microorganisms. Therefore, mycelium-based functional materials represent promising bio-composite materials, especially for biomedical applications.

Nano-scale lipid vesicles or liposomes are extremely important lipid particles because of their unique properties and possible incorporation of various biologically active substances into their interior. Therefore, they can be used for numerous biomedical applications. Liposomes have the ability to protect incorporated bioactive substances, thereby preserving their function. They have a significant advantage over various nanoparticles, as they can bind and transfer hydrophobic, hydrophilic, and amphiphilic compounds. The aim of the study was the synthesis of liposomes, suitable for the potential encapsulation of active ingredients for pharmaceutical and clinical purposes. Liposomes were prepared using a thin lipid film hydration method with glass beads. The synthesized liposomes were characterized by measuring the zeta potential to determine their stability, polydispersity index, and particle size. Furthermore, the biologically active ingredient gallic acid (GA) was incorporated into the lipid vesicles at different concentrations. The encapsulation efficiency of the active ingredient GA in liposomes and the in vitro release of the encapsulated bioactive component were studied using the dialysis technique. Synthesized nano-scale lipid vesicles were found to be stable, with an average size of 181.5 nm. The highest encapsulation efficiency (98.3%) and the highest percentage of released bioactive substance (38.3%) were obtained at 0.1 mg/mL of GA. GA-incorporated nano-scale lipid vesicles are promising as suitable carriers of bioactive ingredients for various therapeutic purposes.

Since various bioactive substances are unstable and can degrade in the gastrointestinal tract, their stabilization is crucial. This study aimed to encapsulate mango peel extract (MPE) into edible alginate beads using the ionotropic gelation method for the potential oral delivery of bioactive substances. Mango peels, generally discarded and environmentally harmful, are rich in health-promoting bioactive substances. The alginate beads were examined for entrapment efficiency, particle size, morphology, thermal stability, physiochemical interactions, release profile under gastrointestinal conditions, and antibacterial efficacy. The study demonstrated the successful encapsulation of MPE with an efficiency of 63.1%. The in vitro release study showed the stability of the alginate beads in simulated gastric fluid with a maximum release of 45.0%, and sustained, almost complete release (99.4%) in simulated intestinal fluid, indicating successful absorption into the human body. In both fluids, the MPE release followed first-order kinetics. Encapsulation successfully maintained the antibacterial properties of MPE, with significant inhibitory activity against pathogenic intestinal bacteria. This is the first study on MPE encapsulation in alginate beads, presenting a promising oral delivery system for high-added-value applications in the food industry for dietary supplements, functional foods, or food additives. Their production is sustainable and economical, utilizing waste material and reducing environmental pollution.

Plant waste materials are important sources of bioactive compounds with remarkable health-promoting benefits. In particular, industrial by-products such as mango peels are sustainable sources of bioactive substances, with antioxidant, enzymatic, and antimicrobial activity. Appropriate processing is essential to obtain highly bioactive compounds for further use in generating value-added products for the food industry. The objective of the study was to investigate and compare the biological activity of compounds from fresh and dried mango peels obtained by different conventional methods and unconventional extraction methods using supercritical fluids (SFE). The highest total phenolic content (25.0 mg GAE/g DW) and the total content of eight phenolic compounds (829.92 µg/g DW) determined by LC-MS/MS were detected in dried mango peel extract obtained by the Soxhlet process (SE). SFE gave the highest content of proanthocyanidins (0.4 mg PAC/g DW). The ethanolic ultrasonic process (UAE) provided the highest antioxidant activity of the product (82.4%) using DPPH radical scavenging activity and total protein content (2.95 mg protein/g DW). Overall, the dried mango peels were richer in bioactive compounds (caffeic acid, chlorogenic acid, gallic acid, catechin, and hesperidin/neohesperidin), indicating successful preservation during air drying. Furthermore, outstanding polyphenol oxidase, superoxide dismutase (SOD), and lipase activities were detected in mango peel extracts. This is the first study in which remarkable antibacterial activities against the growth of Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) and Gram-positive bacteria (Bacillus cereus and Staphylococcus aureus) were evaluated by determining the microbial growth inhibition rate after 12 and 24 h incubation periods for mango peel extracts obtained by different methods. Ethanolic SE and UAE extracts from dried mango peels resulted in the lowest minimum inhibitory concentrations (MIC90) for all bacterial species tested. Mango peels are remarkable waste products that could contribute to the sustainable development of exceptional products with high-added value for various applications, especially as dietary supplements.

Proper processing of natural material is crucial to obtain an extract with high content of biologically active components. Dried, grinded ginger roots were extracted by ultrasonic method and supercritical extraction with CO2. The aim of the study was to determine if a mixture of the two types of extracts attained by different methods and solvents exhibits better bioavailability than each extract itself. Therefore, both extracts were analytically evaluated and then mixed in a ratio of 1:1. The supercritical extract (SCG extract) and the mixed extract (mixG extract) had high antioxidant activity (78% and 73%) and total phenols (827 mg/g ext. and 1455 mg/g ext.), which is also consistent with the levels of gingerol (303 mg/g ext. and 271 g/g ext.) and shogaol (111 mg/g ext. and 100 g/g ext.) in the extracts. In comparison to both pure extracts higher levels of total phenols were found in the extract mixG. This could be the reason for the significant inhibition of melanoma cells and antimicrobial potential (against Staphylococcus aureus, Escherichia coli, and Candida albicans). The combination of the extracts resulted in a significant increase in the inhibition of selected microbial and melanoma cells WM-266-4 compared to the control. Cell viability decreased below 60% when mixG extract was applied. Antimicrobial activity has been confirmed.

This study is focused on different extractions (Cold Maceration (CM), Ultrasonic Extraction (UE), Soxhlet Extraction (SE) and Supercritical Fluid Extraction (SFE)) of bioactive compounds from pomegranate (Punica Granatum L.) fruit peels using methanol, ethanol, and acetone as solvents in conventional extractions and changing operating pressure (10, 15, 20, 25 MPa) in SFE, respectively. The extraction yields, total phenols (TP) and proanthocyanidins (PAC) contents, and antioxidant activity of different extracts are revealed. TP and PAC recovered by extracts ranged from 24.22 to 42.92 mg gallic acid equivalents (GAE)/g and 2.01 to 5.82 mg PAC/g, respectively. The antioxidant activity of extracts ranged from 84.70% to 94.35%. The phenolic compound identification and quantification in selective extracts was done using the LC-MS/MS method. The contents of different flavonoids and phenolic acids have been determined. SFE extract, obtained at 20 MPa, contained the highest content (11,561.84 μg/g) of analyzed total polyphenols, with predominant ellagic acid (7492.53 μg/g). For the first time, Microbial Growth Inhibition Rates (MGIRs) were determined at five different concentrations of pomegranate SFE extract against seven microorganisms. Minimal Inhibitory Concentration (MIC90) was determined as 2.7 mg/mL of SFE pomegranate peel extract in the case of five different Gram-negative and Gram-positive bacteria.